This is by French Impressionist Marcel Dyf (1899-1985). I’ve been unable to find the date for this specific painting, but that’s his signature, and it’s totally his style. He had a thing for flowers in vases.

Fun/creepy fact: At the age of 55, Dyf married 19-year-old Claudine Godat, who appears in many of his paintings:

I don’t know; maybe in the context of 1950s-era France the age difference wasn’t considered as big a deal. They remained married until Dyf’s death in 1985.